Update: This blog was updated July 6 to clarify that this was a zero-day vulnerability attack, not a supply-chain attack.

On the afternoon of Friday, July 2, reports indicated that the REvil ransomware gang was actively targeting managed service providers (MSPs) who use Kaseya Virtual System/Server Administrator (VSA) to manage the networks of other businesses with a zero-day attack.

The attacks result in system lockups due to ransomware.

Kaseya VSA is a cloud-based MSP platform that allows providers to perform patch management and client monitoring for their customers.

According to the July 2nd security advisory from Kaseya, the company recommends that Kaseya VSA users immediately shut down any VSA server until further instructions are given by the vendor. "It's critical that you do this immediately because one of the first things the attacker does is shut off administrative access to the VSA."

Please reference this advisory for more updates.

Trustwave does not use the Kaseya VSA platform. At this time, there is no evidence or reason to believe that the Kaseya supply-chain attack has impacted Trustwave itself.

Trustwave is diligently working with its customers and partners to further determine any impact. Be sure to check your environments for the known indicators of compromise (IoCs) listed below.

If you believe you may have been compromised, please get in touch with the Trustwave Digital Forensics and Incident Response (DFIR) team or your Trustwave support point of contact.

Trustwave will be updating this post with additional pertinent information as it becomes available.

Indicators of Compromise

• Kaseya VSA Detection Tool -- In response to the July VSA Security Incident, Kaseya has created self-assessment scripts for both the VSA Server and associated Endpoints. Please note that while these scripts do not guarantee protection, they can aid in the assessment and identification of vulnerable or affected machines based upon the current known indicators of compromise or IoCs.
• Via Bleeping Computer article
• Via AlienVault Open Threat Exchange
• Via Huntress
• Via Sophos
• Via Unit 42 Palo Alto Networks
• Via Malwarebytes

Global Impact

• Estimated to have led to the encryption of files for around 60 Kaseya customers using the on-premises version of the platform – many of which are managed service providers (MSPs) who use VSA to manage the networks of other businesses
• Approximately 1,500 downstream organizations (customers of MSPs) now affected across ~17 countries
• More than 1 million individual systems are locked up due to ransomware

Mitigations

CISA and FBI recommend affected MSPs:

• Download the Kaseya VSA Detection Tool. This tool analyzes a system (either VSA server or managed endpoint) and determines whether any indicators of compromise (IoC) are present.
• Enable and enforce multi-factor authentication (MFA) on every single account that is under the control of the organization, and—to the maximum extent possible—enable and enforce MFA for customer-facing services.
• Implement allowlisting to limit communication with remote monitoring and management (RMM) capabilities to known IP address pairs, and/or
• Place administrative interfaces of RMM behind a virtual private network (VPN) or a firewall on a dedicated administrative network.

CISA and FBI recommend MSP customers affected by this attack take immediate action to implement the following cybersecurity best practices. Note: these actions are especially important for MSP customer who do not currently have their RMM service running due to the Kaseya attack.

CISA and FBI recommend affected MSP customers:

• Ensure backups are up to date and stored in an easily retrievable location that is air-gapped from the organizational network;
• Revert to a manual patch management process that follows vendor remediation guidance, including the installation of new patches as soon as they become available;
• Implement:
  • Multi-factor authentication; and
  • Principle of least privilege on key network resources admin accounts.

Critical Security Advisories

• Kaseya security advisory
• CISA security advisory

Additional Resources

• Active Reddit thread